This invention relates to key-in-knob locks. More specifically, this invention relates to a system for assembling replacement cylinders for key-in-knob locks.
Prior art conventional key-in-knob cylinders generally comprise a cylinder shell having a rotatable cylinder plug including a keyway. A pin housing or bible, also often refered to as the block or pin housing, of any of a variety of shapes and dimensions projects radially from the cylinder shell. The bible houses the top pins and springs which, together with the bottom pins in the plug, prevent rotation of the key plug relative to the shell without a proper key. Such conventional key-in-knob lock cylinders further include an actuator of any of a variety of shapes and dimensions to transfer rotational motion from the cylinder plug into movement of a latching mechanism inside the lockset. Lock technology has advanced to a level wherein cylinders which are highly pick resistant have been provided in such compact forms that the provision of the radially projecting bible to house top pins and springs is no longer required. Exemplary of the new and improved compact pick resistant locks wherein the locking mechanism is completely housed within the cylindrical body are the locks of U.S. Pat. No. 4,404,824 and of copending application Ser. No. 510,613 filed July 5, 1983 entitled "Side Bar Lock With Enhanced Pick Resistance", now U.S. Pat. No. 4,524,593 and assigned to the assignee of the present invention.
Because of the wide popularity which as been enjoyed by conventional key-in-knob locks, large numbers of the key-in-knob cylinders would be upgraded in the interest of enhanced security if such upgrading could be economically achieved. However, inventory costs for stocking complete cylinders with their many bible and actuator configurations are quite high. The present invention is a new and improved system for assembling replacement high-security key-in-knob cylinders which may be substituted for prior art cylinders which include a shell, plug, bible, and actuator.